Counterbalanced ironing press and operating mechanism



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COUNTERBALANCED IRONING PRESS AND OPERATING MECHANISM Filed July 26, 1943 8 Sheets-Sheet 1 I o 55 I 1/3 A A J73 O 2? Z9 'HIII- 'j I'M/1' Ill} HI H7 1 I i "71 I v ,101 MW,"

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COUNTERBALANCED IRONING PRESS AND OPERATING MECHANISM Filed July 26, 1943 I 8 Sheets-Sheet 2 E. E. FOSTER July 15, 1952 COUNTERBALANCED IRONING PRESS AND OPERATING MECHANISM 8 Sheets-Sheet 5 Filed July 26, 1945 5 I K J13" 79 July 15, 9 E. E. FOSTER 2,603,010

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COUNTERBALANCED IRONING PRESS AND OPERATING MECHANISM Filed July 26, 1943 8 Sheets-Sheet 5 July 15, 1952 E. E. FOSTER 2,603,010

COUNTERBALANCED IRONING PRESS AND OPERATING MECHANISM Filed July 26 1943 8 Sheets-Sheet 6 55. Easter July 15, 1952 E. E. FOSTER COUNTERBALANCED IRONING PRESS AND OPERATING MECHANISM Filed July 26, 1945 8 Sheets-Sheet 7 y 15, 1952 E. E. FOSTER 2,603,010

COUNTERBALANCED IRONING PRESS AND OPERATING MECHANISM Filed July 26, 1943 8 Sheets-Sheet 8 IN V EN TOR.

Eel WL'7Z E l oszeh Patented July 15,. 1952 UNHTEB d CQUNTERBALANCED IRONING PRESS AND I ()PEBATING MECHANISM Edwin E. Foster, Austin, Tex.

Application July 26, 1943, Serial No. 496,189

- 8 Claims.

' This invention relates to an ironing press of the heavy duty type for laundry and dry cleaning purposes. In my co-pending application, Serial No. 379,317, filed February 17, 1941, now Patent No. 2,476,363, dated July 19, 1949, there is object resides in the provision of locking means to latch the head member in the various positions, one'including the extreme open position and another the partially closed position, and

these positions representing the extreme positions of a so-called pendulum stroke of the head member. Another object or" the invention relates to the type of press in which a pre-stressed spring is employed to provide the ironing roe for the 3 head member.

Further objects and aims of the invention will be apparent from the following description, when considered in connection with the accompanying drawings, in which:

Figure l is a side elevation, partly in section of the press in the full open position,

Fig. 2 is a similar View with the parts in the latched down position, with the head and buck spaced a slight distance from each other,

Fig. 3 is a similar view with the parts in a position to preccmpress the material to be pressed with the thickness compensator actuated,

Fig. 4 is a similar View with the parts in the pressing position,

Fig. 5 is a rear elevation of the press with the parts in the position of Fig. 2,

Fig. 6 is a perspective view of frame or t're press,

7 is a perspective view of a yoke of the press,

Fig. 8 is a per pective View of a b ill crank lever,

Fig. 9 is an exploded perspective View of spring. and its link,

Fig. 1G is an exploded perspective View of the thickness compensator,

Fig. 11 is an exploded perspective view of a pedal mechanism, and

Figs. 12 to 14 are perspective views of various detailed elements of the machine.

The press comprises the usual head 'member a bed member or buck 2, ahandle 3 and ,a yoke As seen in Fig.1, the head member i, in the raised position, affords an ideal working clearance above and behind the buck 2, with-fiche handle 3 within easy reach of the operator. The yoke 4 is pivoted at 6 to the upper part of {a frame 5 composed of heavy sheet iron elements welded or otherwise held together toforma rigid box-like structure of angle irons with spaced base plates lili and W2 by means of which the press may be supported or bolted to the door or embedded in concrete.

The yoke 4 and head member i are positively held or locked in'the press openposition, 'Fig. 1, by means of a toggle prop stick or lever 10, 13 which is hinged at one end to the lower end-7 of the yoke i. The prop stick consists of double lower members l0 and a single upper member '13 hinged or pivoted to each other by means. of-a pin 8. The other end of the prop stick is provided with a pin 9 in a bearing 9. which connects the lower links or members Hi with an arrn H- The members it are actually two links withthe single link it pivoted between them atpint at one end and the bearing 9' between the linksjlfl at the other end so that member I3 is single and members It double. The arm H is pivoted to the frame at and by means of a pivot pin 12. The prop stick it and I3 not only serves to latch the head and yoke in the press open but also latches the head I in the partially closed position, Fig. 2, and these two positions constitute a so-called pendulum stroke of the yoke 4 and head member I.

One or more springs M, preferably two,lot which one end is secured to a lug I03 on'an arm Hi l of the yoke 4 and the other end on'a lug I05 secured to the bottom part I86 of the frame 5, are tensioned with sufficient force to throwthe head member I rapidly upward in which position the yoke is latched, Fig. 1. As seen in Fig. 1; the head opening springs 14 are practicallyinline with the pivot point 6 and therefore such springs are not counter-weighting the head i in a manner similar to known machines. The spring It acts to kick the head upwardly from the closed position, but need not exert much force thereon in the raised position as inertia carries the head upwardly into latching position. Y i 1 The handle 3, pivoted at I5 to the yoke-'-4,'is suitably connected by the linkage I07, also connected to the pivot It, to a bell crank lever "i118 pivoted on the underside of the arm I04 at l'08', which acts, when the handle 3 i s moved slightly 'IlQSmD 3h.W.Il., jbac ea a ns esprin sisinm b While downward, to release the prop stick I and [3 so that the head member I falls forward and downward towards the closed position, Fig. 2. In other words the handle member 3 is a lever pivoted at the point l to the yoke 4 and a downward movement on the handle 3 causes the tension link I81 to pull the bell-crank I08 counter-clockwise about its pivot ,T f; pendulum action makes it possilileto utlliz'ef a comparatively heavy cast iron head to be opened and closed quickly with very little efiort, but an aluminum or other metal or alloy head may be used if desired. The force necessary to actuate the head r'edmr'eslittle more" than the weight of the operators hand and arm.

The upper member l3 of the prop stick has a finger I5 secured thereto which is adapted to latch against a roller IT on the end of a double finger I8 secured between the members, ID Fig. 3. The double finger I8 is pivoted at I3 to the member in. A rubber or resilient stop secured to f'eepeeidto the members" In eeuses the toggle stick to' latch op'prog I'i1a e1 vondead center the latch itself will have v ry little load, i5}1th: pgl'r the togg e issiippo'rting considerable w t. The resilient stop 20 is e rned-o a web the toggle mo itor in and is intended to stop mejosoer toggle member 13' just past Where the latch is fully engaged. The toggle members It and I3 'wlth'theelbow at the point 8, break to the fig'litior toward the front of the machine, in Fig. 1; and break npworoin Fig. 2.

second finger 2| cooperates with the lever 108120 the handle 3, while a third finger 22 cooperates witha projection'23' secured on arelease eig'ei 21. 'rhenngers '21 and 22- are pivoted at I; to'aiid between the members H]. "A' tension spring urges the member I8 and theintegral pagers-2| aha 22 anti-clockwise about the pivot point I! on the to'ggleme'mber .Hl. The rounded 'ee mienaor the'finger [6, which is integral with the. toggle" member l3.'is held' by the roller latch foriitliedoiible finger I 8, as shown more clearly in 2. The togglemembersv l0 and I3 are app'rpiumeteiy a straight line, but when the latch member I8 is i'noved'so that the roller rolls-off the end or the member, 1B, the toggle will break upward. The'function of the 'finger 22in breaking thetdggleis to cooperate withthe projection 23.'on "theireleasehpedal 24. When the head is latched down in the position shown in Fig.2. a light touch by the pperators footon the pedal 24 releases the latch at the toggle prop stick llland 13 'and permits the. head I to rapidly return to pen posi iinc heonerat rfsrfi o i i bringing the head downward is an t o time; and a s the pr efibe the spr n Springs impart t the .yokeiwi l. h ffete 'livrrienon and other chenseab evary n re or it is. desirable .to mount the lower end of the toggle member 10,. L3 tohth'e mqvable arm I I at the 'tiearingjfliLand recon ectin arm. ,1! 9 a nramre tcheck 25 by means f jh nsgdfil biv arm ..l.l rests aga nst s iff .gq mp e i m nglllmounted ontop of a post 28, which :iatter is weldedl hesbas nlatellfl 6 fra The purp9 e-.Q. s ar a ement i fl allow; the ;head jto ravel slightly past its two s. 1 and 2, and-then settle the hydraulic check fi permits it to settle back senor... e e were. when we. head I is latched in the open orr'ais'edposition the to gle iprqp stick l0 and l 3 has straightened and latched 21 d. hasy taken ia rm nope/era with it until .h eitif e .bii i irim i h m t o e. as b en reached. The difference between the extreme P9 Y y from position and the actual position at which it comes to rest is the reserve necessary for safety, lest friction should cause the head I not to rise high enough to be latched before starting back down again. The member ll returns against the stop member 21 by means of a tension spring I03, Fig. 11, secured at one end to the base plate l0! and the other end to an extension ill] on the arm I I.

Referring to Fig. 2', it will be noted that the head latches downward or near the closed position in a definite position each time. The padded buck 2 on which the material to be ironed has been placedis moved upward when the operator presses down on a pedal 29, causing a toggle 3i and 89 pivoted together at 30 to straighten. Since the upper member 3| of this buck lifting toggle 3i and 80 consists of a compression spring 3|, the buck 2 will be moved upward more firmly against a thick garment than is the case if a thin garment is on the buck, since the latter is'lifted' by means of the'resilienttoggle. The buck 2' is secured on a supporting neck or post 38 which latter is pivoted on a pin 31 on a guide member 39 pivoted at 6 to the frame 5 on the pin as the yoke 4, as shown in Fig. 1. The pedal 29 is mounted on a rod at 11 on the end of a lever arm 18 which latter is secured on a hub 19 to which'the toggle element 80 is also secured as shown in Fig.1-1.

A wedge member 32 actuated by a tension spring 33 follows through the space between a stationary friction lining member 3'4 and a' movable friction block 35'riiountedon ashoe 36 which latter is pivoted on a pin 31 to a buck supporting neck 38 and a buck supporting arm or guide member ;39, the latterv arm being pivoted on the pin 5. The member 34 is mounted on a cross beam 61 which is welded into the frame .5. The spring 33 is connected to a bell crank lever 89 pivoted at 90 to the frame 5, and as shown in Figs. 1 to 4 a short link 83' connects the lever 88 with the wedge member 32. This tapered wedge 32, which moves into place between the two friction members 34 and 35 as the buck 2 moves upward, keeps the buck from moving back downward as the ironing pressure is applied. Fig. 3 shows the pressure pedal 28 almost down, in which position the buck ,2 is raised firmly again'st whatever material is placed between the head and buck and the wedge 32 has slipped into place holding the pre-compres'sion that was caused by the spring 3|. When the pedal 29 is moved furtherdownward, a lock nut 40 on' the lower end of a tension link 4| is engaged by a flange 42 on a lever arm 18 to which the link 4| is also connected, causing a latch finger 43 to be moved about a pivot point or pm by means of which it is mounted to the frame. The wedge 32 is restored to its original position when the head moves upward, causing a cam 84 to push a roller 85 and a bell-crank 86 about a pivot 81, which pushes a link 88, causing a bell-crank 89 to pivot about a point 90, against the tension spring 33 and pull the wedge 32 to the right by means of the connecting link. This is shown more clearly in Figs. 1 to 4. The weight of the latch finger 43 is sufiicient tocause it to return to the latched position shown in Figs. 1 to 3 when the pedal 23 is restored to its raised position. When the toggle and 3| is broken. the yoke 4 and head member I move upwardly during which movement the cam 84, Fig. 4. rotates counter-clockwise to strike the roller 85, Fig.1, and by the said parts 86, 88 and 89 the wedge member 32isimgved to the right, that'is' restored-to its original poation. This takes place against the force of spring33.

The member ll returns against the stop member 21 by means of a tension spring I09, Fig. 11, secured at one end to' the base plate Hll and the other end to an extension on the arm I I; As shown in Fig. 4 when the latch finger 43 connected to the link 4| by an intermediate link 43, Figs 1 to 4, is lifted from a hub 50, Fig. 3, a U- shaped pivot member-46 and a diamond-shaped leaf compression spring 41 are moved from'the position shown'in Fig. 3 to the position shown in Fig. 4, due to the kick imparted by a compression spring48 through a rod HI, links H and 13 and projection 15. The U-shaped pivot member 46. is actually pivoted on the frame 5 in the lugs 54,"Fig. 6, and the spring 4'! is 'pre-stressed into position between the hubs 5i and 5!], Fig.9. The latch finger 43 contacts hub in Figs. 1 to 3,

but when actuated by the pedal 29 the latch finger is moved upwardly, Fig. 3 to Fig. 4, to thus free the U-shaped member 46. The preleaded leaf spring 41 is hinged to the pivot member 45 by means of suitable bearings 49 and slottedshaft 59, Fig. 9. The compression spring 48 bears on its upper end on the frame 5 as shown in Fig. 4. and the other end against the link or rod 48. The lower end of this diamond-shaped leaf spring fits into a slotted shaft 5] which pivots by means of bearings 52 in the lower end of the yoke member 4. The lower ends of the tension U-member 45 pivot on pins 53 in upright arms or lugs 54, which are welded to a cross support 55, Fig. 6, of the frame 5. The pressure between the head and buck is determined by g the amount of pro-loaded energy that is stored intothe spring 4'], when the press is assembled and it is not dissipated while it is applying pressure, Fig. 4. Since the pivot member 46 and the spring 47 practically float around the pivot points 53 and 5! it is desirable to latch the member 46 in its pressure applied position by means of a latch finger 55 and a roller 51. The roller 51 is mounted on the frame as shown in Fig. 4 by means of a shoulder screw. The latch 56 is held in place in relation to the pedal 24 by means of a tension link 1 l2 backed by a compression spring H3 which presses against a lug H4 on a hub 19. The first part of the release pedal stroke pullsv this latch member 55 oil" the roller 5'! and the continued movement of the release pedal 24 7 causes the pivot member 46 to return to its pressure-off position due to engagement of link l3 and an arm 15 on member 45 shown in Fig. 3, at

which time the latch finger 43 will engage the f roller 45 to hold it against the kick spring 48.

The last part of the stroke of the release pedal 24 also 'unlatches the prop stick toggle andthe head is allowed to open. In actual operation the trip pedal 29 is very easy to operate and a very short stroke. Its ease of operation is aided by means of a counterweight tension spring 58, which counterweights the buck 2 through a lever 59 pivoted on the frame at a point 60 and lifts upward by means of the roller 6!, which contacts against a projection. 62 on the buck guide member '39.

Referring to Fig. 3, the points of coincidence, that is the relation of the pivot point 5! at the lower end of the movable yoke 4 to the stationary point or pivot 53 on which the pivot memr ber 46 hinges is always constant just prior to the head and buck. When the'pressure is applied the toggle prop stick H1, l3 changes from a compression force to a tension force, thereby lifting the hinged member ll away from the stop 21,; as shown in Fig. 11. Since this stroke of the member H is considerably greater during this pressure stroke than at the time the head latches up or down, the hingedlelbow 65 is provided so that the piston of the hydraulic check 25 will not have to go through this extra long travel, but will only lift about /2", this lift being caused by a compression spring 63. As the release pedal 24 is forced downward and the lower end of the yoke 4 falls downward as thepressure is removed, the arm i lowers against the spring stop 21 without any resistance due to the hydraulic check 25, except at the extreme lower end of this stroke. That is, when a stop member 64, Fig; 11, on the arm 65 abuts against the arm I I, the short travel of the lower end of the yoke 4 at the time; the

pressure is applied is caused by the flexing of the yoke and frame membersand the settling of the spring pad and the materials being ironed. Approximately all of this energy is restored to the reservoir spring 41 as the pressure is removed. The upper end of the leaf spring 41, that is, the pivot point betweenthe spring and the U-mem- :ber 48, exactly coincides-with the mainpivot sary to provide additional means, which is the purpose of an arm 65 at the lower end of the buck support 38. This arm 65' is provided with I a roler 66, which rolls against a cross beam 61 which is welded to the frame and which supports the friction block 34. A tension spring 68 attachedito the arm 65 and the frame at the point 69 maintains the roller 66 in contact with the beam 61, as the buck moves up and down.

When the pressure is applied, this roller lifts away from the beam 6'! and stretches the spring 68 due to the forward motion of the head about the pivot point 6.

Referring to the pedals, the release pedal 24 pivots on a shaft in and is on the right hand '56 is also. pinned to the link H at :a point 16.

This hinged link 11 of the release pedal 24 is necessary as it is desirable to be able to open the head by pressing the pedal 24 without having applied pressure, at which time the pedal and projection 23 must release the toggleprop stick latch Without moving the pivot member 46. The

pedal Z i'may forcelever H and connected members l3 and 46 upwardly if the latter are in pressure applying position, but ii the latter are not in pressure applying position, link H connected thereto-may swing up out of the way, so that abutment 23 on the pedal 24 may still function.

The pressure pedal system consists of the pedal 28 pivoted at a point H on a projection 18 which isconnected to a hub 19. A long arm of the buck lifting toggle is also connected to this same hub 19. The hub of the release pedal is also provided with a short arm 98], on'the end of wnig n iefirollanfl; .wmchcooperates with aflat surface- 83 of the: pressure pedal 2-3. Through menrst' art of-the st'rokeof the pedal, the fist-surface 83 reacts against the roller 82, which is stationary until pressure is applied,.and causes the hirblito move-clockwise about the shaft. straightenthetogglemembersiil) and iii to lift the' buckagainst the materials to be ironed. 'rh'e' bracket fl is'a part ofthe arm'lB, and this Brenner 4'2- will-actuate-the release latch 43 :when the pedal-29' ismoved-through-the last part of its spread Astlie pressure is applied',.the roller 82 lifts away fibm the flat" surface of the release pedal-29, asshowni'in-iiig. 4..

' ReIer'i' irig'to Fig. 1,. a cam 84 onth'enriglitliandside ofthe' yoke is in contact with a roller 33. This" rolleris one forked-link B6; whichis pivoted at a point- 81 on the frame; To the lower end of the forked membermi ishinged a curved push link as. The otherend ofthe link 8B} is; connected to an: upright 'nnge'r- 89. on. a eonnter' snart 90. When the: head opens the ca e causesmermemberas andthe push link I! to force the-wedge forwardagainst. the tennon-spring '33, andithe :counterwei'ghted buck .settles-downward as-the wedge is withdrawn. As the head is lowered-thecam fl moves away from the r ollei 35', because the friction shoe 35 keeps mewdge from follov'ving back against the weight of -the buclriin'til theweight or the-buck has been lifted by means o'i the pedal-lii. In 'other'words, the w'edg'e is witnore'wn eaeh time the head goes i115 and: renews back into place only when. the weight or the bu'ck h'as'be'en removed. at which time it follows 'into pla'ce because of the tension spring 33. The counter-weight spring 58:counten-weights all except about 10 or?!) pounds in Orderthat'it'willsttle dO'WlI- eachtim'e With.s11f-- ficien't' weight to hold the wedge, but withnot too much weightwhich would make the wedge hard t6 withdraw and would cause itto chatter.

It is believed that the operation of the ironmg press will be obvious from the foregoing when considered inconnection withrthe drawings. in the full open position of Fig. 1 the article to be pressed is arranged onithe buck 2 after which the operator grasps and pulls on the handle 3 to bring" the head member I down to the position of Fig. 2. Thus when the handle 3 is moved slightly downward about the pivot. l5 the latch in the prop stick I3 is released and'the head moves forward and downward to therpos'iti on of'Fig'. 2. When'the-head is thus latched down alight touch on'the: pedal. releases the latch at the toggle prop stick [0, I3 to-return the head back up to its open position, vif desired for any reason.

v fn the position or Fig. 2 the 'ODGTBiIOl'iIlX'b pressesdown can-the pedal 19 causing the toggle s1 and" at to straighten :thelatter and move the padded buck 2 upward firmly againstthehead I. "I'he wedge member '32 actuated. by the spring 33 will move to "the left between the blocks 34 and 35 maintaining the buck'in place dependent uponthe thickness of the articleto be ironed. Ilie parts are now in the position of Fig. 3 in v'vloich the pressure pedal 29 is almost down and the buck 2 is raised firmly against the article'to be pressed. "When the pedal "29 is now moved 'i'n'i'the'r downward the pivot member 46 and compressed spring '41 will be moved down to the position shown in Fig. 4 to thus apply the force of the spring" 41 between the head and buck and -"pre'ss' the'article between them. To release the head member'it is .merely necessary to press on tlie'l'elease pedal.

I claim .as .my. invention:

1. An ironing press comprising relatively movablehead. and bed. members, means including a collapsibletoggle-prop connected to. the head member for: locking. the. head member in its extreme open position. and for. locking the head member: in a partially-closedposition, the movement oithe head member between the open andpartially closed positions taking place in the collapsed positionof the toggle-prop and repre sentinga stroke of the head member, means-adjacent the. said. toggle-prop for unlocking the head: member, and spring means. associated with the head and bed members-for applyinzaaiorce on the head member: when in contact withthc bed member as an ironing pressure; between the head and bed members to press an article there:- between.

2. An. ironing press comprising a frame, relatively'movable head and bed members mounted on said frame, means including a collapsible t'oggleprop connected to the head member for locking the-head member in its extreme open position and for locking the head member in a partially closed position, the movement of the head member between the open and partially closed positions taking place in the collapsed position of the toggle-prop and representing a stroke of the head member, means adjacent the said toggle-prop for unlocking the head member, and means including a movably mounted prestressedleaf spring and means for moving the spring into a. position so that the force thereof will be applied on the head member against the bed member to thereby apply an ironing pressure between the head and bed members by means of said spring when the latter are in contact with each other to press an article therebetween, said spring being connected at one end to the head member and the other end to the frame of the press.

3. A force applying machine comprising a frame, a bed member mounted on the frame, a head member mounted on the frame and pivoted to open and partially closed positions relative to the bed member, means including a collapsible toggle-prop connected to the head member for latching the head member in the partially closed position, means mounted in the frame for raising the bed member in contact with the head member to completely close the head and bed members, means associated with the mounting .means for the bed member for'locking the bed memberin theposition of contact with .the head member, meansmounted in the frame for unlocking the toggle-prop after the head and bed members are completely closed, and spring means for applying a force on the head member as a pressure force between the head and bed members when in contact with each other.

4. A force applying machine comprising a frame, a bed member mounted on the frame, a .head member mounted on the frame and pivoted to open and partially closed positions relative to the bed member, means connected to vfor locking the bed member in the position of contact with the head member, means mounted in the frame for unlocking the latching means after the headand bed members are completely closed, and spring means for applying a force on the head member as a pressure force between the head and bed members when in contact with each other, said locking means including a wedge between the bed member and the frame of the machine which is spring urged to follow-up the rising movement of the bed member until the latter is in contact with the head member.

5. A force applying machine according to claim 4, in which a pair of members are provided on the raising means of the bed member to frictionally hold the wedge member in the raised position of the bed member.

6. A force applying machine comprising a frame, a bed member mounted in the frame, a head member mounted in the frame and pivoted to open and partially closed positions relative to the bed member, means connected to the head member for latching the head member in the partially closed position, means connected to the bed member for raising the bed member in contact with the head member to completely close the head and bed members, means associated with the raising means for locking the bed member in the position of contact with the head member, means mounted in the frame for unlocking the latching means after the head and bed members are completely closed, and spring means for applying aforce on the head member as a pressure force between the head and bed members when in contact with each other, said latching means including a pair of levers pivoted to each other to form a toggle prop stick when the pivots are in a substantially straight line.

7. An ironing press according to claim 6, in

which means are provided to move the bed member vertically into contact with the head member into its closed position to compensate for different thickness in the material to be pressed.

8. An ironing press according to claim 6, in which latchrelease means are provided connected to the head member and operable therefrom to release the locking means for the extreme open position upon urging the head member toward the closing position.

EDWIN E. FOSTER.

REFERENCES CITED 7 The following references are of record in th file of this patent:

UNITED STATES PATENTS Number Name Date 1,554,511 Leary Sept. 22, 1925 1,562,837 Lindemann Nov. 24, 1925 1,678,464 Diebold July 24, 1928 1,821,670 Sargent Sept. 1, 1931 2,037,551 Visscher Apr. 14, 1936 2,041,923 Hanney May 26, 1936 2,213,689 Bush Sept. 3, 1940 2,231,461 Bush Feb. 11, 1941 2,231,897 Foster Feb. 18, 1941 2,267,467 Johnson Dec. 23, 1941 2,351,956 Graham June 20, 1944 FOREIGN PATENTS Number Country Date 142,415 Great Britain May 6, 1920 654,195 France Nov. 28, 1928 

